The upper class (doctors, lawyers) consumed more food then the working class because they could afford it, yet there was no obesity.
It's not about calories.
It's not about sugar.
It's the PUFAs making us fatigued and sick.
PUFAs are the evolutionary signal for the coming winter and they reduce our metabolic rate which ultimately leads to sickness.
All mammals seek PUFAs when they want to go into hibernation and if you give them a PUFA free diet they will burn through their fat-stores within days.
Listen to this for the quote in the subject: https://youtu.be/QmNzV15Wads?list=PL_7Y5WbwJV_uFMcCRNFbEhmEfV9bLyw2m&t=2142
Then listen to the whole conversation or start at 24:40 to skip the first topic which is specifically about kids.
There are two great channels: "David Gornosksi Fan Favorites" and also "Danny Roddy".
These are the people they have lot's of conversations with:
Brad Marshall (Ex-Keto. Cook, Pigfarmer, Geneticist.) https://fireinabottle.net/
Dr. Ray Peat (Ph.D. in Biology) http://raypeat.com/
Georgie Dinkov http://haidut.me/
Excuse my ignorance about PUFAs but is that just like in non-animal fats? I’ve heard a lot recently about ditching seed oils, and I’ve been doing that. I’ve been eating a lot healthier but I’ve been using tallow, ghee, lard, butter, but also coconut and avocado (both low temp or no heat) but they’re on the PUFA list.
Should I ditch the avocado and coconut?
How about tahini? It’s cold ground sunflower and has oil in it. I love hummus but like I’ve already got some great results from severely reducing and eliminating soy and vegetable oils so I just need to see if I need to take it further.
Edit just to clarify I’ve looked at these links but I don’t really know a lot of chemistry so like slowboy answers appreciated.
PUFAs are poly-unsaturated fats, they are in both animals and plants.
All fats in animals and plants are a mixture of saturated, mono-unsaturated and poly-unsaturated. The classification into "animal" and "plant" is therefore useless.
2 properties distinguish fatty acids:
1.) length (short chain fatty acids, medium, long)
2.) number of unsaturated bonds, which gives them a bend each
Saturated fats are straight, which makes them hard at room temperature (higher density). The more unsaturated a fat is the more bends it has and the lower the melting point is.
In nature there is a important factor that determines your composition of fats and that's temperature.
All warm animals and tropic plants have lots of saturated fats.
All cold animals (fish) and plants have lots of unsaturated fats.
Fortunately grains are still fine because the poly-unsatured parts of the plant are discarded in processing and it has little fat anyway. Same for rice or potatoes.
Avocado and Coconut are great, you will see that they are very high in saturated fats (because they are tropical plants).
The reasoning behind warm animals and plants having different compositions is - among others - the cell membrane. A cell membrane is made mostly of fatty acids and it needs to have a very specific consistency to work. Too hard - doesn't work - dead. Too soft - doesn't work - dead. Your cell membrans would be stiff in a fish and it would die because you have more saturated fats. The cell membrane of a fish in your body would become liquid because it has more unsaturated fats and you'd die as well.
This explains it very well: https://fireinabottle.net/lets-talk-about-fat/
Until recently i would have dismissed that and it's still difficult (i did keto and carnivore for the last 10 years!).
What they say is that starch turns into 100% saturated fats in your body (which is not saying it makes you fat) and the less PUFAs you have in your body the leaner and healthier you get. Not because of calories but because it increases your metabolic rate.